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insects in one treatment. It is therefore desirable that the cultivator 
should be able to recognize insects sufficiently at least to know which 
are more serious at a given time and act accordingly. First among 
such methods we may consider that of plowing with the intention of 
planting the ground with a different crop. 
For many of the insect pests there is no very practicable method to 
apply on a large scale except to plow up the land and put it in some 
other crop for a year or two. The habits of many of the species are 
such that they do not become numerous or particularly injurious in 
grass land until three or four years at least after planting to grass. 
Wire-worms, cut-worms, white grubs, bill-bugs, and also many of the 
Jassidee, Cercopide, Fulgoride, and Acridiidz increase in number from 
year to year until the grass is much reduced in vitality. Such grass 
land is commonly considered to be run out and often thought by eulti- 
vators to have exhausted the soil for grass or to have lost its vitality. 
In reality, I firmly believe this running out is more often due to the 
increase of insects, both subterranean and leaf feeding. The main point 
to be accomplished when a change to another crop is necessary or prat- 
ticable is to arrange the transfer so as to avoid injury to the subse- 
quent crop. Reference to our table will show that for the cutworms, 
wireworms, white grubs, and to some extent probably for the Hemip- 
terous and Orthopterous insects, by far the greater protection to the 
following season’s crop is procured by an early fall plowing—a conclu- 
sion which is supported by practical experience and may, I think, be 
considered thoroughly established. As to times of harvesting, we have 
in the case of the Clover-seed Midge, Clover-seed Caterpillar, Wheat- 
head Army-worm and some other species much to warrant us in the con- 
clusion that early cutting of the crop with prompt storage will accom- 
plish much in the destruction of these insects while still immature. 
The use of fertilizers may be also considered under this head. For 
much of the western country any use of commercial fertilizers is hardly 
to be considered a practicable mode of treatment, but where the use of 
fertilizers upon grass land is in practice, the use of fertilizers which 
have insecticidal properties is no doubt an important means of con- 
tending with insect enemies. The value of such materials has been 
strongly urged by Prof. Smith, who cites experiments indicating the 
destruction of wireworms by the use of kainit. 
In cases where a change is to be made to some other crop, and par- 
ticularly where it is desired to continue a field in grass, trials of this 
substance may well be made with special reference to its insecticidal 
value. 
DIRECT METHODS. 
Direct methods of attack on grass pests will doubtless always be the 
most difficult to enforce. The average farmer seldom appreciates the 
importance of adopting such means sufficiently to use any method 
requiring extra labor or expense. While ready to resort to the rota- 
